I have been very happy with the FEP BCBS. I personally use enough health care that I don't want a HDHP. It is less expensive for me for the insurance and there is no deductible. Also, due to unexpected health events this year I needed a lot more specialist appointments and appreciated not needing to see a PCM for a referral. If you are able to look over past years health costs and calculate out which plan would be cheaper, that would be one way to consider which plan you are interested in. There are quite a few plans available and you can balance things you want (pay less per month, ease of access to care, etc.) vs. the out of pocket costs.
I have never heard a positive story from a single person (fed employee or otherwise) about having a HDHP. Everyone I know who has one as chosen it because the monthly cost is low - and then they are socked with out of pocket costs for every single thing all year until October or something - all the routine visits, vaccinations, an ER visit, illnesses, etc. before the plan even kicks in. They put off appointments or care that is needed because it is expensive and they can't afford the out of pocket costs. This is not a system that would work for me.